Crank-twisting machine



Sept. 15, 1925. 1,553,638

T. SHAW CRANK TWISTING MACHINE Filed Sept. 26, 1925 4 Sheets-Sheet 1 T. SHAW CRANK TWISTING MACHINE mm Sept. 26, 192:

Sept. 15, 1925.

4 Sheets-Sheet 2 ATTORNEY.

Sept. 15, 1925.

T. SHAW CRANK TWIS'IING MACHINE Filed Sept. 26, 1926 4 Sheets-Sheet :5

TlG

A TTORNE Y.

Sept. 15,- 1925. 1,553,638

T. SHAW CRANK TWISTING MACHINE Filed Sept. 26 1923 4 Sheets-Sheet 4 Q F166 I :43 F ME I INVENTOR.

A TTORNEY.

Patented Sept. 15, 1925.

UNITED STATES PATENT OFFICE- 'rnonms sIIAw, or LANSING, MICHIGAN,

ASSIGNO'R TO ATLAS DROP FORGE (10., OF

LANSING, MICHIGAN, A CQRPORATION OF MICHIGAN.

onANxrwIs'rING MACHINE.

Application filed September 26, 1923. Serial No. 664,930.

1 mobile engines and other engines of a similar type having several cylinders, the cranks of which stand at an an le with each other, the crank shaft is first orged with the various throws in a parallel or opposite position and are twisted to the proper an le while hot. My invention relates to e vices for performing this twisting operation, and its purposes are to make a device that shall be rigid in construction; that shall permit of a ready adjustment to secure with the utmost exactness the proper angles, and that shall be substantially automatic in operation.

The form which I have illustrated in the drawings is intended to be operated by steam or compressed air cylinders, but it is evident that it might be manually operated without departing from my invention. As constructed, the air is controlled by a hand valve, not shown.

I attain the purposes of the invention by the means shown in the accompanying drawings in which Figure 1 is a side elevation of my device. The full lines show the position of the parts just after the crank shaft has been introduced into the machine and clamped in place in the loading position. Fig. 2 is a vertical section taken on the line 2-'T2 of Fig. 4. That is, an outer set of rocker arms has been taken away, most of the machine frame or standard has been torn away and the various positions of a second.

and third'set of rockerarms are indicated by full and dotted lines. Fig. 3 shows an elevation of the top position of the machine frame or standard. Fig. 4 shows a plan view of the various dies in the loading position designed to hold the forging to be operated on, the covers and cover clamps for thesefdies being removed. Fig. 5 supple: ments Fig. 2 by showing the position of two of the rocker arms at the end of the operating stroke. Fig. 6 is a detail section, on the line 33 of Fig. 2 which will be explained later. Fig. 7 shows a modification of the linkage and Fig. 8 shows a plan of the same. Fig. 9 shows a plan of the forging before twisting, all bearings and crank pins bein in the same plane. Fig. 10 shows an end e evation of the crank when completed, with crank pins one hundred and twenty degrees apart.

'Referring to the drawings, 1 is the main frame ofthe machine which is largely shown removed in the drawings for the purpose of illustrating the construction and operation.

In the form shown in the drawings,,five floating rocker arms, 11, 12, 13, 14, and 15 are employed. These rocker arms are hinged at their extremities to vertical connecting links, 16, 17, 18, 19, and 20. The rocker arms14 and 15, and the connecting links 19 and 20 are omitted from all the figures except Fig. 4, for purposes of clearness, their construction and operation being precisely the same as rocker arms 12, and 11 and connecting links 17 and '16 respectively. The connecting links 16, 17, 1 8, 19 and 20 are also pivoted to rocker arms 21, 22, 23, and 24. Connecting links 19 and 20 are also pivoted to corresponding rocker arms, mounted on axes 26 and 10, mounted on the frame of the machine. The connectin links '18 are connected at their extremities to rocker arms 24, which are mounted to revolve about axes 25, which are secured to the sides of the rocker arms connected to the connectin links 17 and 19. The axes 25 are offset rom the axes 26 a distance equal to the throw of the proposedlevers 30, which are furnished with friction rollers 37, are provided to lock the various parts of the shaft in position on the dies,

(ill

the inside surface of each of these clamps being formedto fit the corresponding portion of the shaft. Clamps 31 are also mounted on the frame of the machine to lock the shaft in position with reference to the frame and corresponding dies. The device the rocker arms operated by the connecting links 17 and 19, are connected to each other by a cross bar 40 so as to move together. The connecting rods 16 and 20, however, travel entirely independently of each other. Fig. 9 of the drawings shows the crank shaft forging ready for insertion into the machine.

indicate the bearings, and 3-3, 5-5 and 77 the crank pins, 4 represents a chordal member of the shaft connecting the crank pins 3-3, and 5-5. In the complete forging, this member is not radial but is substantially a chord of the circle described by. the crank. pin. For this reason the bearings 2 in the forging are offset slightly from the bearings 6 and are brought back to position in the twisting operation in a manner which will be more fully explained hereafter. The rocker arms 21 are mounted on bearings 10 which are connected, for

' stiffness, by links 39 which in turn, are secured to the frame in any suitable manner. The rocker arms 24 are split through their whole length for convenience in assembling and are held together by bolts 38. The cylinders 32 and 33, are connected to the frame 1 by hinges 54 so as to oscillate. The piston rods 35 are connected to projections 42 on links 18 and 16. Figs. 7 and 8 show a modified construction of my device designed to give increased stiffness against the strain of operation.. The frame of the machine is prolonged upward and inward as shown at43 and the link 18 is prolonged upward to a somewhat higher position as shown at 51. The links 17 and 19 are also prolonged upward in the same manner. A substantially horizontal link 48, extends from the link 17 and is keyed by a key 44 toa bent shaft 49 which re- 'volves in bearings 47 in the upward extensions of the frame 1. The offset in the shaft 49 is precisely; equal to the throw of the crank forging and a bearing 52 is formed at the center, connected by a link 50 to the upward extension ofthe link 18. In this modification, when the link 18 is drawn downward by the action of the cylinder 32, the link 50 simply revolves on the bearing 52. Since the distance between the In this drawing 22 and 66 centers of the link 50 is precisely the same as those of the rocker arms of the link 18, and its position is parallel to them, it will maintain precisely the same relative position and will hold the upper end of the link 18 in that position, during the first part of the stroke. When the links 17 and 19 start downward, however, the links 48 will revolve the shaft 49, giving a motion corresponding to the oif-set of the axes 25 and 26, thus maintaining an exact parallel ism in all the three links concerned and resisting the side strain caused by the cylin der 32 which tends to spring the link 18 outward.

In the modification shown in Figures 7 and 8, the lowest set of rocker arms may be dispensed with, their place being taken by the links 48 and 50 which, being connected with the vertical connection links 17, 18, and 19, give the same parallel motion as is given by the lower set of rocker arms 21-, 22, 23, and 24; the only purpose of the two sets of rocker arms being to give this parallel motion and thus sustain the floating rocker arms in position.

The operation of my device is as follows:

As already stated the crank shaft is first forged with the various cranks parallel to each other; that is, in a plane form, but the function of my device is to twist the various crank arms so that the crank pins will stand at an angle, for six cylinder engines, of 120 degrees with each other, of course, the angle would vary with the number of cylinders.

With all ofthe floating rocker arms in their loading position and the clamps open the hot forging is placed on the dies and all the clamps are locked by the levers 30.

Steam or compressed air is then turned into the cylinders. While in actual operation, the cylinders might operate in any order or simultaneously, for convenience in explanation, I prefer to start with the action of cylinder 32. This draws down'link 18 carrying with it rocker arm 13. This acts on crank pins 7, raising and revolving them counter clock-wise through an angle of 60 degrees. The twisting comes on bearings 2 which are held stationary meanwhile. This is the position indicated by the full lines in Fig. 2.- \Vhen this motipn is completed the rocker arm 24 engages with the cross bar 40 connecting the rocker arms 17 and 19, and carries them. along with iii in its. motion through an additional angle of 30 degrees until the rocker arm 22 engages the stop 27 as shown in .Fig. 2. During this operation the twist comes on crank pins 33 which are held still. Inthe meantime the bearings 2-2, because of the off-set of the axes 25 and 26, will have been carried to a new position as indicated in Fig. 3, carrying with them crank pins 77 and pleting the operation; An end View ofthe shaft will then give the appearance shown in Fig. 10. In this position the bearings 6-45 and 2-42 will have'been brought exactly into line with each other and the crank pins will stand at an angle of 120 degrees with each other, the crank pins 3 and 5 being connected by the chordal members 4, while the crank pins 5 are connected tothe bearing 6 by .radial throws 53. All the clamps are then loosened and thrown back. Air is then turned into the'opposite end of the cylinders and the operation reversed. The links rise, carrying with them their corresponding rocker arms until the projection 41 engages with the cross bar 40, then carries with it the rocker arms 22 until they engagethe stop 36, thus locking the entire device in the open position ready to receive another forging.

I claim as my invention and desire to secure by Letters Patent:

1. The combination in a character described, of a main frame, provided at its upper extremitywith clamps adapted to releasably hold a forging in position; a plurality of floating rocker arms also provided with clamps adaptedto releasably engage with said forging; links connected to the opposite extremities of each of said rocker arms for retaining saidfloating rocker arms in cooperative relationship to each other and to said first mentioned clamps, and means for revolving said rocker arms about their respective centers of revolution.

2. The combination in a device of the character described, of a main frame, provided at its upper extremity with clamps adapted to releasably retain a forging in position; a plurality of floating rocker arms also provided with clamps adapted to engage with said forging; links connected to the opposite extremities of each of said floating rocker arms; parallel motion rocker arms supported on relatively fixed axes and having their extremities connected to said links so as to give a arallel motion thereto and means for revolving said first mentioned rocker arms about their respective axes. Y

3. The combination in a device ofthe character described, of a main frame, prodevice of the.

vided at its upper extremity with clamps adapted to releasably retain a forging in position; a plurality of floating rocker arms also provided with clamps adapted to releasably engage said forging;- links connected to the opposite-extremities of each of said floating rocker arms; a plurality of parallel motion rocker arms supported on said frame, all of said rocker arms having their extremities connected to said links so as to give a parallel motion thereto;'and a plurality of arallel motion rocker arms each of which has its axis mounted on one of said last mentioned rocker arms.

4. The combination in a device of the character described, of a main frame, provided at its extremities with clamps adapted to releasably retain a forging in position; a. pair of rocker arms revolubly mounted on fixed axes on said frame; links connecting the opposite extremities of each pair of said', rocker arms and a floating rocker arm hinged to the extremities of said links and provided with clamps adapted to releasably engage with said forging.

5. The combination in a device of the character described, of a main frameprovided at itsextremities with clamps adapted to releasably retain a forging in position; two pair of rocker arms revolubly mounted on fixed axes on said frame; links connecting the opposite extremities of each pair of said rocker arms, and a floating rocker arm hinged to the extremities of each pair of said links and provided with clamps adapted to releasably engage with said forging. 6. The combination in a device of the character described, of a main frame provided at its extremities with clamps adapted to releasably retain a forging in position; two pairs of rocker arms revolubly moimted on fixed axes on said frame; a pair of rocker arms revolubly mounted on axes connected to said first mentioned rockerarms; links connecting the opposite extremities of each pair of said rocker arms, and a floating rocker arm hinged to the extremities of each pair of said links and provided with clamps adapted to releasably engage with said forging.

7. The combination in a device of the character described, of a mainframe provided at its extremities with clamps adapted to releasably retain a forging in position; two pairs of rocker arms revolubly mounted on fixed axes on said frame; a. ,pair of rocker arms revolubly mounted on axes con nected to said first mentioned rocker arms;

two pairs of rocker arms revolubly mounted on axes attached to said frame outside of and concentric with said first mentioned axes; links connecting the opposite extremities of each pair of said rocker arms, and a floating rocker arm hinged to the extremities of each pair of saidlinks and provided with clamps adapted to releasably engage with said forging.

8. The combination in a device of the character described, of a main frame pro- 5 vided at its extremities with clamps adapted to releasably retain a forging in posifiion; parallel motion gocker arms revolubly mounted on fixed axes on said frame; parallel motion links connected to the free extremities of saidrocker arms; and a floating arm hinged to said links and provided with a clamp adapted to releasably engage said forging.

THOMAS SHAW. 

